BACKGROUND: The role of acute-stage transmission in sustaining HIV epidemics has been difficult to determine. This difficulty is exacerbated by a lack of theoretical understanding of how partnership dynamics and sexual behavior interact to affect acute-stage transmission. We propose that individual-level variation in rates of sexual contact is a key aspect of partnership dynamics that can greatly increase acute-stage HIV transmission. METHODS: Using an individual-based stochastic framework, we simulated a model of HIV transmission that includes individual-level changes in contact rates. We report both population-level statistics (such as prevalence and acute-stage transmission rates) and individual-level statistics (such as the contact rate at the time of infection). RESULTS: Volatility increases both the prevalence of HIV and the proportion of new cases from acute-stage infectors. These effects result from 1) a relative reduction in transmission rate from chronic but not acute infectors and 2) an increase in the availability of high-risk susceptibles. CONCLUSIONS: The extent of changes in individual-level contact rates in the real world is unknown. Aggregate or strictly cross-sectional data do not reveal individual-level changes in partnership dynamics and sexual behavior. The strong effects presented in this article motivate both continued theoretical exploration of volatility in sexual behavior and collection of longitudinal individual-level data to inform more realistic models.
BACKGROUND: The role of acute-stage transmission in sustaining HIV epidemics has been difficult to determine. This difficulty is exacerbated by a lack of theoretical understanding of how partnership dynamics and sexual behavior interact to affect acute-stage transmission. We propose that individual-level variation in rates of sexual contact is a key aspect of partnership dynamics that can greatly increase acute-stage HIV transmission. METHODS: Using an individual-based stochastic framework, we simulated a model of HIV transmission that includes individual-level changes in contact rates. We report both population-level statistics (such as prevalence and acute-stage transmission rates) and individual-level statistics (such as the contact rate at the time of infection). RESULTS: Volatility increases both the prevalence of HIV and the proportion of new cases from acute-stage infectors. These effects result from 1) a relative reduction in transmission rate from chronic but not acute infectors and 2) an increase in the availability of high-risk susceptibles. CONCLUSIONS: The extent of changes in individual-level contact rates in the real world is unknown. Aggregate or strictly cross-sectional data do not reveal individual-level changes in partnership dynamics and sexual behavior. The strong effects presented in this article motivate both continued theoretical exploration of volatility in sexual behavior and collection of longitudinal individual-level data to inform more realistic models.
Authors: Martin Hoenigl; Antoine Chaillon; Sanjay R Mehta; Davey M Smith; Joshua Graff-Zivin; Susan J Little Journal: J Infect Date: 2016-08-11 Impact factor: 6.072
Authors: Mirjam E Kretzschmar; Maarten F Schim van der Loeff; Paul J Birrell; Daniela De Angelis; Roel A Coutinho Journal: Proc Natl Acad Sci U S A Date: 2013-09-05 Impact factor: 11.205
Authors: Ganna Rozhnova; Maarten F Schim van der Loeff; Janneke C M Heijne; Mirjam E Kretzschmar Journal: PLoS Comput Biol Date: 2016-08-01 Impact factor: 4.475
Authors: Patrick Janulis; Steven M Goodreau; Michelle Birkett; Gregory Phillips; Martina Morris; Brian Mustanski; Samuel M Jenness Journal: J Acquir Immune Defic Syndr Date: 2021-07-01 Impact factor: 3.771